mobile army surgical hospital

from The Collaborative International Dictionary of English v.0.48
MASH \MASH\, MASH \M*A*S*H\, n. (Mil.)
   An abbreviation for {Mobile Army Surgical Hospital},
   consisting of the equipment and personnel required to perform
   emergency operations on injured soldiers, located in tents
   near the front lines of combat; as, he worked in the 25th
   MASH.
   [PJC]
    

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